nucleation and growth based on the assessment of material damage accumulation. The suggested simulation scheme takes into account the heterogeneity of the material fatigue resistance, the closure effect and elastic-plastic material response. The proposed technique considers the crack initiation phase and allows performing crack growth calculations in areas with significant plastic strain. The approach has been used to model the three-dimensional crack propagation from internal cavity until its occurrence on the outer surface in non-continuous filletwelded joint. It is shown that the life scatter of the weld joint is affected by the crack nucleation stage. The results of life calculation accounting for the initial material inhomogeneity and obtained crack front evolution are in good agreement with the published experimental data.

Keywords: weld joint, fatigue, damage accumulation, fatigue crack, FEM, microstructure, life scatter.

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